Sony Xperia Zl — Mobile issue and poor phone service

Address:

Gujarat

I have purchased Sony Xperia ZL C- 6502 on 24-3-13. There was a problem of mic in my phone. I gave my phone at Avani Electronics (Authorised Service center) Gandhidham on 18th of june 2013. I was informed that they will service and would inform us. When I did follow up they informed me that they will change the mic so would take time but when I went to collect my phone on 28th of june, they handed over my phone saying that there was no major problem and they didn't change the mic, just serviced it. Fine, things went well, phone started well.
But recently other problem started. Now my front camera (12 MP) is having some issue. When I am starting it, its showing around 8-9 black small dots in camera and photos taken by main camera. I called toll free Sony xperia care and tried to understand the problem and tried to understand the history of my phone service as I never had a problem in main camera before the service station visit. I spoke to xperia care executive and came to know that during the service at Gandhidham sony center, 2 more parts were changed that were front camera (2.2 mp) and camera switch. Surprised. I had never complained about this. We were never informed about these 2 parts in written and oral when we went to recollect the phone. When I spoke to Gandhidham service station, they said that they changed these parts because they felt that parts were also not upto the mark so they changed it. I am surprised because they changed those parts which were working good and just serviced mic which was supposed to be replaced which was having problem in both incoming and outgoing calls.
In addition to that when I went to collect my phone, they handed over some other phone instead of my phone.
It looks like having worst experience from sony authorised service center. Service is not upto the mark.
I understand the value of Sony brand as I am one of the biggest Sony fan, have used sony mobiles in the past and currently having Vaio as well. But after this experience, I feels that Sony is not bothered for quality product and efficient service.
Already my phone has visited one time during the first 3 months of purchase and even problem is not solved but multiplied.
I have purchased this phone with my harden money to have a nice high end tech. android phone costing 35k (upgraded from live with Walkman) but looks like I have wasted my money on a defective phone. I am looking for the replacement of my phone instead of going all the time to service center and changing parts here and there. Looking for the quick conclusion.

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